Financial firms once supported only the BlackBerry, but now Apple's iOS and the iPhone and iPad are gaining momentum across the Street.

Research In Motion (RIM) once owned Wall Street, but consumer demand for Apple products is changing the way Wall Street firms are looking at their mobile device of choice. Many firms are opening the doors to multiple devices, such as the iPhone, iPad and smartphones using Google's Android operating system.

Most financial services firms have been traditionally RIM shops, offering their employees only one smartphone or email device, and it has always been the BlackBerry. Security and compliance issues around allowing other unapproved or consumer devices to access the financial firm's private network have always been the main concern.

But consumer behavior is changing that once-common practice. Greg Lavender, Citi's CTO of Infrastructure Engineering, says supporting Citi's increasingly mobile workforce is "about employee empowerment. You embrace it and provide structure or it will happen anyway."

Citi, once a BlackBerry-only shop, has changed its ways -- six months ago it started implementing a "bring your own device," or BYOD, strategy. The reason? To make it easier on employees to use the device with which they are already comfortable and to allow workers to carry a single device, rather than one for work and another for personal use.

John D'Onofrio, Citi's Chief Technology Officer, noted that Citi is a long-time RIM customer with more than 40,000 BlackBerry devices deployed around the world. "These devices are primarily used to access our network for email services as well as browser-based delivery of applications," D'Onofrio says. "However, Citi has also developed 20 to 30 internally native BlackBerry applications for certain specific business requirements. The RIM platform, being locked down and tightly controlled, allows us to provide security and manageability that meets our requirements."

He adds, "We are certainly on track to adopt a bring-your-own-device strategy. We are moving away from provisioning devices for people to provisioning environments in which they can do their jobs that are fully secured. As part of that we are changing a lot of our network capability to enhance that -- in some cases putting in additional security to protect against rogue attacks from an outside device."

According to D'Onofrio, Citi is moving away from a desktop-centric work environment toward Citi's internal cloud-enabled application setup. Employees will have full access to their applications from any device, including corporate desktops and personal devices.

The financial services firm has been working on this for the past six to eight months, but a lot of the work is still getting off the ground, D'Onofrio explains. In the short time the transformation has been underway, the firm already has a "heavy" number of iPad users and a "significant" number iPhone users, he reports. And Citi expects to see growth in that usage, especially on the iPhone side.

The solution that Citi has deployed to secure email is from Good Technology, which many financial services organizations are using to secure mobility solutions and enable employees to connect and collaborate on their device of choice.